Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 662	$ 53
Accounts receivable, net of allowance for doubtful accounts:
Oil and natural gas	227	220
Joint operations and other	241	238
Derivative instruments	135	4
Prepaid costs and other	39	31
Total current assets	1,304	546
Property and equipment:
Oil and natural gas properties, successful efforts method	19,710	18,476
Accumulated depletion and depreciation	(7,904)	(7,390)
Total oil and natural gas properties, net	11,806	11,086
Other property and equipment, net	234	216
Total property and equipment, net	12,040	11,302
Funds held in escrow	60	43
Deferred loan costs, net	15	11
Intangible asset - operating rights, net	24	24
Inventory	14	16
Noncurrent derivative instruments	90	0
Other assets	44	177
Total assets	13,591	12,119
Current liabilities:
Trade	26	28
Revenue payable	129	132
Accrued drilling costs	446	359
Derivative instruments	0	82
Other current liabilities	165	152
Total current liabilities	766	753
Long-term debt	2,741	2,741
Deferred income taxes	1,212	766
Noncurrent derivative instruments	0	96
Asset retirement obligations and other long-term liabilities	143	140
Commitments and contingencies (Note 9)
Stockholders' equity:
Common stock, $0.001 par value; 300,000,000 authorized; 149,314,618 and 146,488,685 shares issued at June 30, 2017 and December 31, 2016, respectively	0	0
Additional paid-in capital	7,108	6,783
Retained earnings	1,686	884
Treasury stock, at cost; 591,650 and 429,708 shares at June 30, 2017 and December 31, 2016, respectively	(65)	(44)
Total stockholders' equity	8,729	7,623
Total liabilities and stockholders' equity	$ 13,591	$ 12,119